Field of the Invention
The present disclosure relates to a manufacturing method of a part-mounting package.
Description of the Related Art
A part-mounting package includes, for example, a plate-like substrate base having a substrate front surface, a substrate rear surface, and substrate side surfaces. This substrate base has, for example, a multilayer structure including laminated multiple insulating layers and multiple conductor layers. Furthermore, this package may have end face through-hole conductors formed in the substrate side surfaces.
Conventionally, there has been proposed various compact ceramic packages for accommodating an electronic part such as a quartz resonator, a quartz oscillator, and a quartz filter (see, for example, JP-A-2010-73711). FIG. 20 illustrates an example of a conventional ceramic package 80. The ceramic package 80 has the multilayer structure including a plurality of ceramic insulating layers 81 and 82 (ceramic sintered layers) and is provided with a cavity 83 opened at its upper face. A part connection terminal 84 to be connected to the electronic part is provided in a part (for example, a bottom surface) of the cavity 83. Furthermore, external connection terminals 85 to be connected to an external substrate, a through-hole conductor 86, end face through-hole conductors (castellation) 87, wiring patterns 88 of the internal layer (conductor layers), a sealing conductor layer 89, and so on are formed in the ceramic package 80.
The end face through-hole conductors 87 are formed in four corners in the ceramic package 80, respectively. In more detail, in the side surface of each corner of the ceramic package 80, a side surface recess part 90 recessed in the shape of a quarter arc are provided. Further, the end face through-hole conductors 87 are formed in a lower region 91 (the region corresponding to the ceramic insulating layer 82 in the lower layer side) of the side surface recess parts 90. Further, the end face through-hole conductor 87 is connected to the part connection terminal 84 and the sealing conductor layer 89 via the wiring pattern 88 of the internal layer and the through-hole conductor 86.
Here, a manufacturing method of the conventional ceramic package 80 illustrated in FIG. 20 will be exemplified. It is noted that the ceramic package 80 is manufactured by a multi-cavity technique. That is, first, a large size package having a plurality of product regions aligned vertically and horizontally on a flat face is manufactured. Subsequently, it is divided to obtain individual packages 80.
Specifically, first, a conventional known punching (stamping) is applied to a ceramic green sheet made of a ceramic material. Thereby, a through-hole for the through-hole conductor 86, through-holes for the end face through-hole conductors 87, and so on are formed. It is noted here that the through-holes formed for the end face through-hole conductors 87 have a same size both within the green sheet as the ceramic insulating layer 81 in the upper layer side and within the green sheet as the ceramic insulating layer 82 in the lower layer side. Next, a conductive paste is printed on the wall surface of the through-hole. Then, a conductive paste is printed and formed on the surface of the ceramic green sheet so that a predetermined pattern according to the circuit wiring to be formed is resulted. A conventional known punching is then applied to the ceramic green sheet. Thereby, a through-hole for the cavity 83 is formed.
Then, a plurality of ceramic green sheets is laminated, a predetermined weight is applied thereto in the thickness direction by using a conventional known laminating apparatus to press and integrate them, and thereby the ceramic green sheet laminated body is formed. Here, the ceramic green sheets are laminated while positioning the through-holes for the end face through-hole conductors 87 in each ceramic green sheet so that these through-holes are vertically overlapped.
Then, a grooving in the ceramic green sheet laminated body is performed by a laser irradiation by using a laser machining apparatus, and a plurality of laser division grooves for obtaining divided individual product regions is formed. At this time, the grooving is performed so that two laser division grooves 94 intersect at the center of the through-hole 93 for the end face through-hole conductor 87 (see FIG. 21). In a subsequent firing process, this laminated body is heated at a predetermined temperature at which alumina can be sintered. In the laminated body after this firing, each ceramic green sheet and the conductive paste have been sintered. In this way, a large size ceramic package is obtained. In each of the product regions in this package, formed are metalized conductor layers such as the part connection terminal 84, the external connection terminals 85, the through-hole conductor 86, the end face through-hole conductors 87, the wiring patterns 88 of the internal layer, and the conductor layer 89.
Further, the metalized conductor layers such as the wiring patterns 88 of the internal layer, the through-hole conductor 86, and the end face through-hole conductors 87 is utilized to supply a current to the metalized conductor layers such as the part connection terminal 84 and the conductor layer 89. A plating layer is then formed on the metalized conductor layers such as the part connection terminal 84 and the conductor layer 89 by a nickel electroplating and a gold electroplating. Furthermore, the large size ceramic package is divided along the laser division grooves 94 and thereby a plurality of ceramic packages 80 is obtained at once.